Process for breaking petroleum emulsions employing certain oxyalkylated tris (hydroxymethyl) aminomethanes



July 12, 1960 M. DE GROOTE ETAL 2,944,983 PROCESS FOR BREAKING PETROLEUM'EMULSIONS EMPLQYING CERTAIN Filed June 10, 1954 BUTYLENE OXIDE I00 7,

T'RIS (HYDROXYMETHYL AMINOMETHANE United States Patent r 2,944,983PROCESS FOR BREAKING PETROLEUM EMUL- SIONS EMPLOYING CERTAINOXYALKYLATED TRIS(HYDROXY1VIETHYL)AMINOMETHANES Melvin De Groote,University City, and Owen H. Pettingill, Kirkwood, Mo., assignors toPetrolite Corporation, Wilmington, Del., a corporation of Delaware IFiled June 10, 1954, Ser. No. 435,669 20 Claims. (Cl. 252--344) Thisinvention relates to processes or procedures particularly adapted forpreventing, breaking or resolving emulsions of the water-in-oil type,and particularly petroleum emulsions.

Our invention provides an economical and rapid process for resolvingpetroleum emulsions of the water-in-oil type that are commonly referredto as cut oil, roily oil, emulsified oil, etc., and which comprise finedroplets of naturally-occurring waters or brines dispersed in a more orless permanent state throughout the oil which constitutes the continuousphase of the emulsion.

It also provides an economical and rapid process for separatingemulsions which have been prepared under controlled conditions frommineral oil, such as crude oil and relatively soft waters or weakbrines. Controlled emulsification and subsequent demulsification underthe conditions just mentioned are of significant value in removingimpurities particularly inorganic salts, from pipeline oil.

More specifically then, the present invention is concerned with aprocessfor breaking petroleum emulsions employing a demulsifierincluding a cogeneric mixture of a homologous series of glycol ethers oftris(hydroxy.- methyl)aminomethane.'- The cogeneric mixture is derivedexclusively from tris(hydroxymethyl)aminomethjane, ethylene oxide andbutylene oxide in such weight proportions so the average composition ofsaid cogeneric mixture stated in terms of initial reactants liesapproximately within theS-sided figure of the accompanying drawing inwhich the minimum tris(hydroxy rnethyl) aminomethane content is at least1.75% and which S-sided figure is identified by the fact that its arealies within the straight lines connecting A, B, C, D, and H. 7

We have found that when tris(hydroxymethyl)aminomethane is combined withbutylene oxide and ethylene oxide in certain proportions andparticularly when the butylene oxide is employed first, followed by useof ethylene oxide and more especially if the butylene oxide employed isone of the straight chain isomers OH OH--- \r; CH2 CH5 CHrCH- -CHOHs ora mixture of the two and if the composition falls within the limitsindicated by the sided figure on the hereto attached triangular chart,said derivatives are of unusual efiectiveness for a number of purposesparticularly when surface activity is a factor, either directly orindirectly. One example is the use of such derivatives in the resolutionof petroleum emulsions of thewater-inoil type. v

In a general way the compounds whichhavebeen found most effective andfall within the limits of the- In another series parts oftris(hydroxymetliyl):

aminomethane have been reacted with 6 parts by weight a asserts l p t ntfi Jufiy 12,

of butylene oxide and 85 parts by weight of ethylene oxide. In anotherseries 1.5 parts by weight of tris(hydroxymethyhaminomethane have beenreacted with 13.5 parts by weight of butylene oxide and 85 parts byweight of ethylene oxide. Similarly, in another series the followingcombinations have been used: 1.5 parts of tris (hydroxymethyl)aminomethane combined with 58.5 parts by weight of butylene 'oxide and40 parts by weight of ethylene oxide; 20 parts by weight oftris(hydroxymethyl) aminomethane, reacted with 40 parts by weight ofbutylene oxide and then with 40 parts by weight of ethylene oxide. Inanother series 20 parts by weight of tris(hydroxymethyl)aminornethanewere reacted with 10 parts by weight of butylene oxide and then 70 partsby weight of ethylene oxide.

It is of interest to note in some instances as little as 1.75 parts oftris(hydroxymethyhaminomethane may be combined with 98.25 parts of thetwo oxides to produce very valuable derivatives.

We have also found that where part of the butylene oxide is replaced bypropylene oxide, i.e., where a combination oftris(hydroxymethyl)aminomethane, butylene oxide, propylene oxide andethylene oxide are used, effec tive and valuable surface-active agentscan also be obtained. This, however, represents a separate invention.

For the purpose of resolving petroleum emulsions of the water-in-oiltype, we prefer to employ oxyalkylated derivatives, which are obtainedby the use of monoepoxides, in such manner that the derivatives soobtained have suflicient hydrophile character to meet at least the testset forth in U.S. Patent No. 2,499,368, dated March 7, .1950, tovDeGroote and Keiser. In. said patent such test for emulsification using awater-insoluble solvent, generally xylene, is described as an index ofsurface activity;

fication test, simply means that the preferred product fordernulsification is soluble in a solvent having hydro- .phobe propertiesor in an oxygenated .water insoluble or even a fraction of aWater-soluble-hydrocarbon solvent and that when shaken with water theproduct may remain in,the nonaqueous-solvent or, for that matter, it maypass into the aqueous solvent. In other words, although it is xylenesoluble, for example, it mayalso be water soluble to an equal or greaterdegree.

- .For purposes of convenience what is said hereinafter will be dividedinto three parts:

Part 1 is concerned with the oxyalkylation oftris(hydroxymethyDaminomethane in general;

Part 2 is concerned with the oxyalkylation oftris(hydroxymethyl)aminomethane using two difierent oxides, i.e.,butylene oxide and ethylene oxide so as to produce derivatives fallingwithin certain composition limitations hereinafter noted in detail. Forconvenience, Part 2 is divided into two sections, Section A is concernedwith .oxybutylation and oxyethylation broadly, and Section B isconcerned with the particular composition corresponding to the hereinspecified compositions and illustrate such combinations;

rAR'r 1 -At the present time there is available butylene oxide whichincludes isomeric mixtures, for instance, one manufacturer haspreviously supplied a mixed butylene oxide which is in essence a mixtureof l-butene oxide, Z-butene oxide isomers and approximately 10%isobutylene oxide. Another manufacturer has supplied an oxide which isroughly a fifty-fifty mixture of the cisand trans-isomers of 2-buteneoxide.

There is also available a butylene oxide which is characterized asstraight chain isomers being a mixture of the 1,2 and the 2,3 isomersand substantially free from the isobutylene oxide.

This latter product appears to consist of 80% of the 1,2 isomer and 15%of the mixed 2,3 cisand 2,3 transisomer. We have obtained the bestresults by using an oxide that is roughtly 80% or more of the 1,2 isomerand with either none, or just a few percent if any, of the isobutyleneoxide, the difference being either form of the 2,3 or a mixture of thetwo forms.

Our preference is to use an oxide substantially free from theisobutylene oxide, or at least having minimum amounts of isobutyleneoxide present.

Since the varying solubility of different butanols is well known, it isunnecessary to comment on the effect that the varying structure has onsolubility of derivatives obtained by butylene oxide. Purely by way ofexample, the applicants have tested the solubility of the first twoavailable butylene oxides and noted in one instance the butylene oxidewould dissolve to the extent of 23 grams in 100 grams of Water, whereasthe other butylene oxide would only dissolve to the extent of 6 grams in100 grams of water. These tests were made at 25 C.

As to further reference in regard to the isomeric butylene oxides seeChemistry of Carbon Compounds, volume I, part A, Aliphatic Compounds,edited by E. H. Rodd, Elsevier Publishing Company, New York, 1951, page671.

As to the difference in certain proportions of the cisand trans-form ofstraight chain isomers 2,3-epoxybutane see page 341 of A Manual ofOrganic Chemistry, volume 1, G. Malcolm Dyson, Longmans, Green andCompany, New York, 1950.

Reference to butylene oxide herein of course is to the compound orcompounds having the oxirane ring and thus excludes 1,4-butylene oxide(tetrahydrofurane) or a trimethylene ring compound.

When reference is made to the oxides, for instance, ethylene oxide andbutylene oxide, one can use the corresponding carbonates. Ethylenecarbonate is available commercially. Butylene carbonate, or thecarbonate corresponding'to a particular oxide, is not availablecommercially but can be prepared by the usual methods in the laboratory.For this reason further reference to the alkylene carbonates will beignored although it is understood When oxyethylation takes place bymeans of ethylene carbonate one could, of course, use butylene carbonatefor oxybutylation.

In the present invention we have found that outstanding products areobtained by the use of certain preferred butylene oxides, i.e., thoseentirely free or substantially free (usually 1% or less) and composed ofapproximately 85% or more of the =l,2 isomer with the remainder, if any,being the 2,3 isomer.

In the preparation of the outstanding compounds We have studiouslyavoided the presence of the isobutylene oxide as far as practical. Whenany significant amount of isobutylene oxide happens to be present, theresults are not as satisfactory regardless of the point when thebutylene oxide is introduced. One explanation may be the following. Theinitial oxybutylation which may be simplified by reference to amonohydric alcohol, produces a tertiary alcohol. Thus the oxybutylationin the presence of an alkaline catalyst may be shown thus:

Further oxyalkylation becomes difiicult when a tertiary alcohol isinvolved although the literature records successful oxyalkylation oftertiary alcohols. This does not necessarily apply when oxyalkylationtakes place in the presence of an acidic catalyst, for instance, ametallic chloride such as ferric chloride,stannic chloride, aluminumchloride, etc. We are not completely satisfied that oxyalkylation oftris(hydroxymethyl)aminomethane in presence of an acidic catalyst maynot cause some degradation, possibly etherization or dehydration takesplace. The situation is somewhat akin to sorbitol which involves similarderivatives. Thus, oxyalkylation under such conditions may involvetris(hydroxymethyl)aminomethane in part and may involvetris(hydroxymethyl) aminomethane degradation products in part and alsomay involve water in part. We have tried procedures such as using analkaline catalyst and tris (hydroxymethyl)aminomethane, employing about4 to 6 moles of isobutylene oxide. Afterwards, an amount of acid wasadded equal to the amount of caustic used as a catalyst and the reactionmass was dried and then stannic chloride added. Under such circumstancesthe results suggest more satisfactory oxybutylation. as such althoughthe procedure becomes cumbersome, uneconomical and perhaps evenimpractical.

This, however, seems to be only a partial explanation. Anotherexplanation may rest with the fact that isobutylene oxide may show atendency to revert back to isobutylene and oxygen and this oxygen maytend to oxidize the terminal hydroxyl radicals. This possibility ispurely a matter of speculation, but may account for the reason we obtainmuch better results using a butylene oxide as specified. In regard tothis reaction, i.e., possible conversion of an alkylene oxide back tothe olefin and nascent oxygen, see Tall Oil Studies II, Decolorizationof Polyethenoxy Tallates With Ozone and Hydrogen Peroxide, .T. V.Karabinos et al., J. Am. Oil Chem. Soc. 31, 71 (1954).

In order to illustrate why the herein contemplates compounds or saidproducts are cogeneric mixtures and not single chemical compounds, andwhy they must be described in terms of manufacture, and molal ratio orpercentage ratio of reactants, reference is made to a monohydricalcohol. Tris(hydroxymethyl) aminomethane is a polyhydric alcohol having3 reactive hydrogen atoms attached to oxygen and also 2 attached tonitrogen. Thus, for the present purpose it might be considered the sameas an amino alcohol having 5 hydroxyl radicals. However, for the moment,one can forget the hydrogen atoms attached to nitrogen and even theplurality of hydroxyl radicals and simply consider what happens When amonohydric alcohol is subjected to oxyalkylation,

If one selects any hydroxylated compound and subjects such compound tooxyalkylation, such as oxyethylation, it becomes obvious that one isreally producing a polymer of the alkylene oxide except for the terminalgroup. This is particularly true Where the amount of oxide added iscomparatively large, for instance, 10, 2'0, 30, 40, or 50 units. If sucha compound is subjected to oxyethylation so as to introduce 30 units ofethylene oxide, it is well known that one does not obtain a singleconstituent which, for sake of convenience, may be indicated as RO(C HO) H. Instead, one obtains a cogeneric mixture of closely relatedhomologous compounds in which the formula may be shown as the following:RO(C H O),,H, wherein n, as far as the statistical average goes, is 30,but the individual members present in significant amount may vary frominstances where n has a value of 25 and perhaps less, to a point where nmay represent 35 or more. Such mixture is, as stated, a cogenericclosely related series of touching homologous compounds. Considerableinvestigation has been made in regard to the distribution curves forlinear polymers. Attention is directed to the article entitledFundamental Principles of Condensation Polymeriza- .pentaerythritol,dipentaerythritol, etc.

tion," by Paul J. Flory, which appeared in Chemical Reviews,volume39,No.1, page 137. I

Unfortunately, as has been pointedout by Flory and other investigators,there is no satisfactory method, based on either experimental ormathematical examination, of indicating the exact proportion ofthevarious members of touching homologous series which appeanincogeneric condensation products of thekinddescribed. .;Thisymeans thatfrom the practical standpoint,: i.e.,.the abilit'y to describe how tomake the .productunder consideration and how to repeat such production"time after time without difliculty, it is necessary to resor't to someother method ofdescription. a v 7 E What has been saidinregardtQamQnohydric compound of course is multiplied many times inthe;,ase of a polyhydric compound such vas tris(hydroxyrn ethyl)aminomethane. This is particularlytrue even in regard to ethylene oxidealone but becomes even more complitype of apparatus. The capacitywasapproximately 4 liters. The stin'eroperate'd at a speed of,approximately 250 r.p.m. There were charged into theautoclave 500 gramsof tris(hydroxymethyl) aminomethane, 300 grams of xylene, and grams ofsodium methylate. The autoclave was sealed, swept with nitrogen gas andstirring started immediately and heat applied; The temperature wasallowed to rise to approximately gfimg C. At this Oxide.

' added in this operation was:1-500 grams. The time recated whenbutylene oxide isiused in light of What has been said previously inregard to the-isomers of butylene oxide.

PART 2 Section A The oxyalkylation of an amine, particularlyra primaryamine or secondary amine or ahydroxylated .amine regardless of. whetherit is primary, secondary, or tertiary, is comparatively simple and hasbeen described repeatedly in the literature. If the product is a liquidsuch as. triethanolamine one can proceed to treat with analkyle'ne'oxide such as ethylene oxide,- propylene oxide,

quired to add the butylene oxide was two hours. During this period thetemperature was maintainedat 135 to 150 C, using cooling water throughthe inner coils when necessary and otherwise applying heat if, required.The maximum pressure during the reaction was 7 pounds per square inch.Ignoring the xylene and sodium methylate and considering the only tris(hydroxymethyl)- aminomethane forconvenience, the resultant productrepresent 3 parts by weight of butyleneoxide to one part by weight oftris(hydroxymethyl)aminomethane. The xylene present representedapproximately. .6 ,of'one part byweight. f e Example"2a The reactionmass was transferred to a larger autoclave (capacity 15 liters). Withoutadding any more cata lyst or any more xylene the procedure was repeatedso as to add another 1500 grams of butylene oxide under alkylation israther extensive as in the present instance,

one requires a catalyst after the initial stage and j it .is-

just as simple to add it from the very beginning. If the amine isa'solid at ordinary temperature and this istrue;

in regard to tris(hydroxymethyl)aminomethane, one can readily follow theprocedure of using a slurry in the same manner that is employed inconnection with other solids although not necessarilynitrogen-containing. Reference is made toproducts such as sorbitol,sucrose, glucose,

'-Specific reference is made to the instant application which isconcerned with ethylene oxide,-.and butylene oxide, or the equivalents.Actually, whether one uses ethylene oxide or butylene oxide, onepreferably starts with either the powdered famine suspended as a slurryi in xylene or a similar inactive solvent; or oneemploys an alkylenecarbonate such as ethylene carbonate or butylene carbonate, forthe'initialoxyalkylation. When such initial oxyalkylation has gone farenough to convert the solid mass into a product which is at least liquidat oxyalkylation temperature it can be subjected to the oxides asdiiferentiated from the carbonates. The carbonates, of course, cost morethan the oxides.

In any event, any one of a number of well known procedures may beemployed and reference has been made to U.S. Patent No. 2,652,394, datedSeptember 15, 1953, to De Groote. This particular patent happens to beconcerned with sucrose but, as a matter of fact, one can just as readilysubstitute tris(-hydroxymet'hyl)aminomethane and the reaction will gojust as rapidly and, in fact, perhaps more rapidly than with sucrose.Referring to said aforementioned patent, the same procedure usingpropylene oxide, or ethylene oxide, can be employed simply usingbutylene oxide insteadx It is not believed any examples are necessarytoillustrate such well known procedure but for purpose of illustration thefollowing are included: i

I I Example In.

The reaction vessel employed was a stainless steel autoclave withitheusual devices for heating, heat. control, stirrer, inlet, outlet, etc.,which is conventional in this up'andrequired approximately 6 hours,using the same .operating temperatures and pressures. The ratio at theend of the third step was 9.25 parts byweight of butylene substantiallythe same operating conditions but requiring about 3 hours for theaddition. At the end of this step the ratio represented approximately 6to 1 (ratio butylene, oxide to tris(hydroxymethyl) aminomethane.

Example 3a 'In a third step, instead of adding 1500 grams of butyleneoxide, 1625 grams were added. The reaction slowed oxide per weight oftris(hydroxymethyl)aminomethane.

Example 4a At the end of this step the autoclave was opened and anadditional 5 grams of sodium methylate added, the autoclave fiushedoutas before, and the fourth and final oxyalkylation completed, using 1625grams of butylene oxide, and the oxyalkylation was complete within 3%hours using the same temperature range and pressure as previously. Atthe end of the reaction the product represented approximately 12.5 partsof butylene oxide by weight to one part oftris(hydroxymethyl)aminomethane.

' All the examples, except the first step, were substantiallywater-insoluble and xylene-soluble.

As has been pointed out previously these oxybutylated tris(hydroxymethyl) aminomethane were subjected to oxyethylation in the samemanner described in respect to the oxypyropylated sucrose inaforemention U.S. Patent No. 2,652,394. Indeed, the procedure iscomparatively simple for the reason that one is working with a liquidand also that ethylene oxide is more reactive than butylene oxide. As aresult, using the same amount of catalyst one can oxyethylate morerapidly than usually at a lower pressure. There'i's no substantialdifierence as far as operating procedure goes whether one isoxyethylating oxypropylated tris(hydroxymethyl)aminomethane oroxybutylated tris(hydroxymethyl)aminomethane.

The same procedure using'a slurry of tris(hydroxynection with ethyleneoxide and the same mixture on a percentage basis was obtained as in theabove examples where butylene oxide and tris(hydroxymethyl)aminomethanewere used.

The same procedures have been employed using other butylene oxidesincluding mixtures having considerable catalyst such as sodiummethylate, caustic soda, or th like.

Actually, tris(hydroxyrnethyl)aminomethane at times may contain a traceof moisture. Our preference is' to isobutylene oxide and mixtures of thestraight chain isoprepare the slurry with an excess of xylene anddistill mers with greater or lesser amounts of the 2,3 isomer. off apart of the xylene so as to remove any trace of Where reference has-beenmade in previous examples water and then flush out the mass withnitrogen. Even to 'the straight chain isomer, the product used was oneso, there may be a few tenths of a percent of moisture which wasroughlyl85% or more of the 1,2 isomer and remain although at timesexamination indicates at the approximately of. the2,3-cisand the2,3-transiso- 10 most it is merelyatrace. 'mer with'substantially noneor not over 1% of the iso- PART 2 butylene oxide. 1

In the preceding procedures'one oxide has been added swim" B and thenthe other. One need not follow this proc In light of what has been saidpreviously, particularly The two oxides can be mixed together insuitable pro- 1 in Section. A, it is ehvious that hardly any directionsare portions and subsequently subjected to jq fl o y y required toproduce the compounds herein specified. as to Q i i PI Commg Wlthm hspec'lfled However, referring to the composition of the initialrelimits. In such IDStEDCBg'Of course, the oxyalkylation aetants basedon the 5 Sided fight-e in the attttehed draw; may be described as randomoxyalky-lation insofar that hlg, t m he noted we have calculated thepercentage one cannot determine the exact location of the butylene thethree initial reactants the points A, B, C, D oxide or ethylene oxidegroups. In such instances the E F, G, H, I and I which appear on theboundary f the procedure again is identically the same as previously de-5 figure and also determine the five subdivided F F 5 tfl f we have usedF math parts of the 5-sided figure, two parts being triangles and odsconnectlon, with msmydroxymethyl)ammome'th' the others being twopar-allelograms, and one trapezoid. j t Likewise we have calculated thecomposition for a num- If desired, one may add part of one oxide and allof b jf examples i hi m area of h graph and the other and then return tothe use of the first oxide, responding to points 1 to 18, inclusive.Note these data for instance; or one may use the procedure aspreviously, are included in Table I, immediately following:

TABLE I Tertiary Mixture, Percent Binary Intermediate Mixtures,

Basis Percent Basis Points on Boundary Tris(l1y- Tris(l1y- Tris(hyofArea droxy- Butyl- Ethyldroxy- Butyldroxy- Ethylmethyl) ene ene methyl)ene methyl) ene emiuo- Oxide Oxide amino- Oxide amino- Oxide methanemethane methane adding first some butylene oxide, then ethylene oxideand then the butylene oxide. Or, inversely, one may add some ethyleneoxide, then all butylene oxide and then the remainder-[of the ethyleneoxide; or either oxide could be added in portions so that first oneoxide is added, then the other, then the first oxide is added again, andthen the second oxide. We have found no advantage in so doing. Indeed,our preference has been to add all the butylene oxide first and then therequired amount of ethylene oxide. 7

Any suitable catalyst which promotes oxyalkylation may be employed,provided its use is not incompatible with the use of an alkylenereactant, especially in the initial stage. It is .our preference,however, to use a Note the first column gives the particular point onthe boundary of the 5-sided figure or within the 5-sided figure area.Note the next three columns represent the tertiary mixture whichcorresponds to the initial reactants, to wit, the percentages, byweight, of tris (hydroxymethyl)aminomethane butylene oxide and ethyleneoxide. Thus it is apparent that onecould select any particular point andsimply use the appropriate number of pounds of oxide; for instance, inregard to a point A all that would be necessary would be to mix 5 poundsof butylene oxide with pounds of ethylene oxide and use the mixture tooxyalkylate 10 pounds of tris(hydroxymethyl)- aminomethane.

Similarly, in Example B, one need only mix 13.5

pounds of butylene oxide with 85 pounds of ethylene oxide and use themixture to oxyalkylate 1.5 pounds of tris(hydroxymethyl) aminomethane.

Note the fifth and sixth columns represent binary intermediate mixtures.For instance, in regard to the various-points onlthe boundary and withinthe -sided figure area, we have calculated the initial mixture usingtris(hydroxymethybaminomethane and butylene oxide in the first case, andusing tris(hydroxymethyl)aminomethane and ethylene oxide in the secondcase, which would be employed for subsequent oxyalkylation to give theparticular composition required. Note that abinary intermediate for thepreparation of point A can be prepared in any suitable manner involving66.6% of his- (hydroxymethyl)aminomethane and 33.4% of butylene oxide;Thus, for example, one could use 66.6 pounds of tris(hydroxymethyl)aminomethane and 33.4 pounds of butylene oxide, or on a larger scale onecould use 666 pounds of tris(hydroxymethyl)aminomethane and 334 poundsof butylene oxide. Referring now to the tertiary mixture table, it isapparent that for point A tris(hydroxyrnethyl) aminomethane and butyleneoxide together represent 15%, andethylene oxide 85%.

pounds of ethylene oxide. v

Similarly, in regard to the fifth and sixth columns for. point B, theinitial mixture involved tris(hydroxymethyl)- aminomethane and butyleneoxide, representing 110% of tris(hydroxymethyl) aminomethane and 90% ofbutylene oxide. If desired, pounds of tris(hy'droxymethyl)-'aminomethane could be reacted with 90 pounds of butyl; ene oxide. Suchmixture need only be reacted with Therefore, one could employ 7 a poundsof the binary mixture and react it with 85.,

ethylene oxide by reacting 15v poundsYof the mixture with 85 pounds ofethylene oxide. This is obvious from the data in regard to the tertiarymixtures.-

Referring now to columns 7 and 8, itris obvious one could readilyproduce an oxyethylated tris(hydroxymethyl)aminomethane and then subjectit *toreac'tion with butylene oxide. Using this procedure in regard toA. it is obvious that the mixture represents 10.5 of tri's-(hydroxymethyDaminomethane and 89.5% of ethylene oxide. This productcould be obtained from a'binary mixture of 105 pounds oftris(hydroxymethyl)aminomethane and 895 pounds of ethylene oxide.

Referring now to the. tertiary'mixture table, it is obvious that 95pounds of such mixture couldbe reacted with 5 pounds of butylene oxideto give point A. Similarly, in regardto point B the oxyethylatedtris(hydroxymethy1)aminomethane represents 1.7% of tris(hydroxymethyl)aminomethane and 98.3% ethylene oxide. The mixture so obtained byreferring to the tertiary mixture table would be reacted with'butyleneoxide in the proportion of 86.5 pounds of the mixture and 13.5 pounds ofbutylene oxide.

As previously pointed out, the oxyalkylationof tris- (hydroxymethyl)aminomethane, orcomparable hydroxylated amines has been described in theliterature and is described also in detail above. ploy such conventionaloxylation procedure to obtain products corresponding to the compositionsas defined. Attention is. again directed to the fact that one need notadd the entire amount of either oxide at one time but that a smallportion of one could be added and then another small portion of theother, and the processrepeated.

Purely for purpose of illustration, we have prepared examples threedifierent ways corresponding to the compositions shown on the chart. Inthe first series the .butylene oxides and ethylene oxide were mixed;this series is indicated as An, Ba, through and including 18a; in thesecond series butylene oxide was used first followed by ethylene oxideand this series indicated Ab,

Eb, through and including 18b; and finally in the third series ethyleneoxide was used followed by butylene oxide All one need do is ernsensesTABLE II Composition Composition Composition where Butylwhere Ethyl-Composltion Corresponding where Oxides ene Oxide ene Oxide to FollowingPoint are Mixed Used First Used First Prior to Oxy- Followed by Followedby alkylation Ethylene Butyleuo Oxide Oxide Aa Ab Ac Ba B1; B0 Ca Ob CcDa Db Dc Ea Eb Ec Fa Fb Fa Ga Gb Go Ha Hb Hc Ia Ib Ic Ia J1; J0 1a 1b 1c2a 2b 2c 30 3b 31: 4a 4b 4a 6a 5b 50 6a 6b '6c 7a 7b 7c 8a 8b 80 9a 9b90 10a 10b 10: 11a 11b 110 12a 1211 124: 13a 13b 13C 14a 14b 140 15a 15b15c 16:: 16b 162 17a 17b 17c 18a 18b 18c lent amount of acid, such ashydrochloric acid. For

many purposes the slight amount of residual alkalinity is notobjectionable.

, There are certain variants which can be employed without detractingfrom the metes and bounds of the invention, but for all practicalpurposes there is nothing to be gained by such variants and the resultis merely increased cost. For instance, any one of the two oxides can bereplaced to a minor percentage and usually to a 1 very small degree, byoxide which would introduce sub stantially the same group along with aside chain, for in stance, one could employ glycidyl methylether,glycidyl ethyl ether, glycidyl isopropyl ether, glycidyl butyl ether orthe like.

Increased branching also may be efiected by the use of an imine insteadof a glycide, or a methyl glycide. Thus one can use ethylene imine, orpropylene imine in the same way described for glycide or methyl glycide.An additional effect is obtained due to the basicity of the nitrogenatom. The same thing is true as far as the inclusion of nitrogen atomsif one uses a compound of the kind previously described such as adialkylaminoep oxypropane. Excellent products are obtained by reactingtris(hydroxymethyl)aminomethane with one to six moles of ethylene imineand then proceeding in the same manner herein described.

In the hereto appended claims reference has been made to glycol ethersof tris(hydroxymethyl)aminomethane." Actually it well may be that theproducts should be referred to as polyol ethers oftris(hydroxymeth'yl)aminomethane in order to emphasize the fact that thefinal products of reaction have more than two hydroxyl radicals.However, the products may be considered as hypothetically derived byreaction of tris(hydroxymet-hyl) aminomethane with the glycols, such asethylene glycol, butylene glycol, propylene glycol, or polyglycols. Forthis reason there seems to be a preference to use the 11 terminologyglycol ethers of t-ris(hydroxymethyl)aminoethane.

PART 3 As to the use of conventional demulsifying agents, reference ismade to US. Patent No. 2,626,929, dated January 7, 1953, to De Groote,and particularly to Part 3. Everything that appears therein applies withequal force and effect to the instant process, noting only that wherereference is made to Example 13b in said text beginning in column 15 andending in column 18, reference should be to Example 18b, hereindescribed.

Having thus described our invention, what we claim as new and desire tosecure by Letters Patent is: 1

1. A process for breaking petroleum emulsions of the water-in-oil typecharacterized by subjecting the emulsion to a demulsifying agentincluding cogeneric mixture of a. homologous series of glycol ethers oftris(hydro xymethyl)aminomethane; said cogeneric mixture being derivedexclusively from tris(hydroxymethyl) aminomethane, ethylene oxide andbutylene oxide in such weight proportions so the average composition ofsaid co'gene'ric mixture, stated in terms of initial reactants, liesapproximately within the 5-sided figure of the accompanying drawing inwhich the minimum tris (hydroxymethyl) aminomethane content is at least1.75% and which 5- sided figure is identified by the fact that its arealies within the straight lines connecting A, B, C. D, and H.

2. The process of claim 1 with the proviso that oxyalkylation takesplace in presence of an alkaline catalyst.

3. The process of claim 1 with the proviso'that oxyalkylation takesplace in presence of an alkaline catalys and that the butyleneoxide beadded first.

4. The process of claim 1 with the proviso that oxyalkylation takesplace in presence of an alkaline catalyst and that the butylene oxide beadded first, and with the further proviso that the butylene oxide issubstantially free from isobutylene oxide.

5. The process of claim 1 with the proviso that oxyalkylation takesplace in presence of an alkaline catalyst and that the butylene oxide beadded first, and with the further proviso that the butylene oxideconsists of 85 or more of the 1,2-isomer and approximately 15% or lessof the 2,3-isomeric form, and is substantially free from isobutyleneoxide.

6. The process of claim 5 with the proviso that the reactant compositionfalls within the triangular area defined by C, D, and E.

7. The process of claim 5 with the proviso that the reactant compositionfalls within the parallelogram D, E, F, and J.

8. The process of claim 5 with the proviso that the reactant compositionfalls within the parallelogram J, F, G, and I.

9. The process of claim 5 with the proviso that the reactant compositionfalls Within the trapezoid I, G, B, and H.

10. The process of claim 5 with the proviso that the reactantcomposition falls within the triangle H, B, A.

11. A process for breaking petroleum emulsions of the water-in-oil typecharacterized by subjecting the emulsion to a demulsifying agentincluding a cogeneric mixture of a homologous series of glycol ethers oftris (hydroxymeth'yl)aminomethane; said cogeneric mixture being derivedexclusively from tris(hydroxymethyl)- aminomethane, ethylene oxide andbutylene oxide in such weight proportions so the average composition ofsaid cogeneric mixture, stated in terms of initial reactants, liesapproximately Within the S-sided figure of the accompanying drawing inwhich the minimum tris(hydroxymethyD-aminomethane content is at least1.75% and which 5-sided figure is identified by the fact that its arealies within the straight lines connecting A, B, C, D, and H; with theproviso that the hydrophile properties of said cogeneric mixture in anequal weight of xylene are sufficient to produce an emulsion when saidxylene solution is shaken vigorously with one to three volumes of water.

12. The process of claim 11 with the proviso that oxyalkylation takesplace in presence of an alkaline catalyst.

13. The process of claim 11 with the proviso that oxyalkylation takesplace in presence of an alkaline catalyst and that the butylene oxide beadded first.

14. The process of claim 11 with the proviso that oxyalkylation takesplace in presence of an alkaline catalyst and that the butylene oxide beadded first, and with the further proviso that the butylene oxide issubstantially free from isobutylene oxide.

15. The process of claim 11 with the proviso that oxyalkylation takesplace in presence of an alkaline catalyst and that the butylene oxide beadded first, and with the further proviso that the butylene'oxideconsists of or more of the 1,2-isomer and approximately 15% or less ofthe 2,3-isomeric form, and is substantially free from isobutylene oxide.

16. The process of claim 15 with the proviso that the reactantcomposition falls within the triangular are defined by C, D, and E.

17. The process of claim 15 with the proviso that the reactantcomposition falls within the parallelogram D, E, F, .and J.

18. The process of claim 15 with the proviso that the reactantcomposition falls within the parallelogram J, F, G, and I.

19. The process of claim 15 with the proviso that the reactantcomposition falls within the trapezoid I, G, B, and H.

2 0. The process of claim 15 with the proviso that the reactantcomposition falls within the triangle H, B, A.

References Cited in the file of this patent UNITED STATES PATENTS2,233,383 De Groote Feb. 25, 1941 2,262,736 De Groote et a1 Nov. 11,1941 2,290,416 De Groote et al. July 21, 1942 2,457,634 Bond et al. Dec.28, 1948 2,552,530 De Groote May 15, 1951 2,574,544 De Groote Nov. 13,1951 2,589,200 Monson Mar. 11, 1952 2,622,099 Ferrero et al. Dec. 16,1952 2,649,483 Huscher et al. Aug. 18, 1953 2,677,700 Jackson et al. May4, 1954

1. A PROCESS FOR BREAKING PETROLEUM EMULSIONS OF THE WATER-IN-OIL TYPECHRACTERIZED BY SUBJECTING THE EMULSION TO A DEMULSIFYING AGENTINCLUDING COGENERIC MIXTURE OF A HOMOLOGOUS SERIES OF GLYCOL ETHERS OFTRIS(HYDROXYMETHYL) AMINOMETHANE, SAID COGENERIC MIXTURE BEING DERIVEDEXCLUSIVELY FROM TRIS(HYDROXYMETHYL) AMINOMETHANE, ETHYLENE OXIDE ANDBUTYLENE OXIDE IN SUCH WEIGHT PROPORTIONS SO THE AVERAGE COMPOSITION OFSAID COGENERIC MIXTURE, STATED IN TERMS OF INITIAL REACTANTS, LIESAPPROXMATELY WITHIN THE 5-SIDED FIGURE OF THE ACCOMPANYING DRAWING INGTHE MINIMUM TRIS(HYDROXYMETHYL) AMINOMETHANE CONTENT IS AT LEAST 1,75%AND WHICH 5-